The reference tables purchasing and shop teams use most: dash sizes, thread dimensions by connection family, and DIN tube series. Bookmark this page — or print it and tape it to the bench.
Dash size chart
Hydraulic sizes use dash numbers: the dash is the nominal size in sixteenths of an inch. A -08 fitting is 8/16" = 1/2".
| Dash |
Nominal |
Dash |
Nominal |
| -02 |
1/8" |
-12 |
3/4" |
| -03 |
3/16" |
-14 |
7/8" |
| -04 |
1/4" |
-16 |
1" |
| -05 |
5/16" |
-20 |
1-1/4" |
| -06 |
3/8" |
-24 |
1-1/2" |
| -08 |
1/2" |
-32 |
2" |
| -10 |
5/8" |
-40 / -48 / -64 |
2-1/2" / 3" / 4" |
JIC 37° flare threads (SAE J514)
| Dash |
Tube OD |
Thread (UNF/UN) |
| -02 |
1/8" |
5/16-24 |
| -03 |
3/16" |
3/8-24 |
| -04 |
1/4" |
7/16-20 |
| -05 |
5/16" |
1/2-20 |
| -06 |
3/8" |
9/16-18 |
| -08 |
1/2" |
3/4-16 |
| -10 |
5/8" |
7/8-14 |
| -12 |
3/4" |
1-1/16-12 |
| -14 |
7/8" |
1-3/16-12 |
| -16 |
1" |
1-5/16-12 |
| -20 |
1-1/4" |
1-5/8-12 |
| -24 |
1-1/2" |
1-7/8-12 |
| -32 |
2" |
2-1/2-12 |
ORFS threads (SAE J1453)
| Dash |
Tube OD |
Thread (UN) |
| -04 |
1/4" |
9/16-18 |
| -06 |
3/8" |
11/16-16 |
| -08 |
1/2" |
13/16-16 |
| -10 |
5/8" |
1-14 |
| -12 |
3/4" |
1-3/16-12 |
| -16 |
1" |
1-7/16-12 |
| -20 |
1-1/4" |
1-11/16-12 |
| -24 |
1-1/2" |
2-12 |
SAE ORB port threads (SAE J1926-1)
| Dash |
Thread (UNF/UN) |
| -02 |
5/16-24 |
| -03 |
3/8-24 |
| -04 |
7/16-20 |
| -05 |
1/2-20 |
| -06 |
9/16-18 |
| -08 |
3/4-16 |
| -10 |
7/8-14 |
| -12 |
1-1/16-12 |
| -16 |
1-5/16-12 |
| -20 |
1-5/8-12 |
| -24 |
1-7/8-12 |
NPT / NPTF nominal sizes (ASME B1.20.1)
| Nominal |
Threads per inch |
Approx. male OD |
| 1/8" |
27 |
0.41" |
| 1/4" |
18 |
0.54" |
| 3/8" |
18 |
0.68" |
| 1/2" |
14 |
0.84" |
| 3/4" |
14 |
1.05" |
| 1" |
11.5 |
1.32" |
| 1-1/4" |
11.5 |
1.66" |
| 1-1/2" |
11.5 |
1.90" |
| 2" |
11.5 |
2.38" |
BSP nominal sizes (ISO 228 / ISO 7)
| Nominal |
Threads per inch |
Approx. male OD |
| 1/8" |
28 |
0.38" |
| 1/4" |
19 |
0.52" |
| 3/8" |
19 |
0.66" |
| 1/2" |
14 |
0.83" |
| 3/4" |
14 |
1.04" |
| 1" |
11 |
1.30" |
| 1-1/4" |
11 |
1.65" |
| 1-1/2" |
11 |
1.88" |
| 2" |
11 |
2.35" |
DIN 2353 metric tube series
| Series |
Tube OD range |
Typical use |
| LL (extra light) |
4–12 mm |
Lubrication, instrumentation |
| L (light) |
6–42 mm |
General hydraulics, medium pressure |
| S (heavy) |
6–38 mm |
High-pressure hydraulics |
Need help reading a measurement? See the thread identification guide, or contact us with caliper readings and two photos.